Circuit-breaker.



F. J. CLEAVER.

CIRCUIT BREAKER.

APPLICATION FILED 110v.1.1915.

wnuzss: I mvzm-on.

ATTORNEY UNITED STATES PATENT OFFICE.

FREMONT J. CLEAVER, OF CARNEGIE BOROUGH, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO HERBERT W. HODGDON, OF PITTSBURGH, PENNSYLVANIA.

CIRCUIT-BREAKER.

proved breaker for electric circuits.

The object in view is the provision of a circuit breaker which willautomatically interrupt the circuit when an abnormal rise in currentoccurs without destroying any portion or element of the breaker, and

through which the circuit may be quickly restored without theintroduction or substitution of any new element or portion.

I accomplish thesepurposes by providing an air-tight receptacle ofglass, or other suitable material of non-conductive character, having,..preferably integral therewith, an internal open top reservoir or cutinto which extend the terminals of the electric circuit to be protected.The reservoir is normally'filled with an unstable fluid conductor,preferably mercury, which electrically connects said terminals andcompletes the circuit between the same. The quantity of such fluidconductor is regulated to safely carry the normal current, but when anabnormal rise in'current occurs, said fluid conductor expands orvaporizes so as to flow over the open top of the reservoir and thusdestroy the electrical connection for the pas- V sage of the normalcurrent, owing to the lack of sufiicient fluid conductor remaimng in theI reservoir to carry the normal current from one terminal to the other.

The-"circuit may be instantaneously restored by. rotating or invertingthe receptacle to refill the reservoir and electrically recon.- nectingthe terminals. I show an improved mounting of the breaker whereby thelatter may be rotated or inverted for refilling without its removal fromthe switch board or displacement from the circuit in' which it isinterposed.

In he accompanying'drawings, Figure 1 is a longitudinal section of myHHPI'OVGdcircuit breaker, showing the same mounted rotatively. in springcontact clamps; Fig. 2 is a cross sectional view of the same along theline II-II in Fi 1; Fig. 3 is a vertical section of a modifie form ofsaid breaker, and

Specification of Letters Patent.

Patented June 5, 191 *7.

Application filed November 1, 1915. SerialNo. 58,947.

Fig. 4 is a sectional view of the same along the line IVIV in Fig. 3.

The following is a detailed description of the drawings.

A is a hermetically sealed receptacle of glass or other non-conductingmaterial, preferably in the form of a cylinder with closed ends, andhaving its exteriorends threaded,

as shown. Within said recefptacle is the open top reservoir 1,preferably ormed integrally onthe wall of the receptacle, as shown. Band C are stout copper circuit terminals extending through the walls ofthe receptacle and protruding into the ends of the reservoir 1. Theouter ends of said terminals are provided. with enlarged contact plates2 which are brought into close electrical contact with the inner facesof the heads of the a brass end caps D and E which are screwed onto thethreaded ends of the receptacle A,

as shown. The circuit breaker is mounted in the circuit to be protectedby interposing the brass capsD and E between the spring contact clamps Fand G of the switch board or other support, H. An insulated handle orknob I is mounted on one end of the breaker, so that the latter may berotated without removing it from the contact clamps.

3 represents a quantity of fluid conductor of unstable character, suchas mercury, filling the reservoir-.1 'and electrically connecting theterminals B and C under normal current. When an abnormal rise in currentoccurs, the mercury expands or vaporizes, thus causing the same to flowover the open top of the reservoir and prevent the resumption of theflow of normal current between the terminals, owing to an insuflicientquantity of mercury remaining inthe reservoir. The electrical connectionbetween the terminals is thus interrupted and the circuit broken.

By rotating the receptacle in the direction of the. arrow in Fig. 2, theempty reservoir is turned, mouth rst, down through the mercury in thelowest portion of the receptacle and rises into its normal position onthe other side refilled with mercury, thus reestablishing the circuitbetween the terminals B and C.

The receptacle may be. rotated to refill the reservoir without removingthe breaker from the spring contact clamps of the switch board, bygrasping theknob I.

The excess {i of mercury facilitates the refilling of the reservolr, asabove described.

The interior of the reservoir is preferably a vacuum or a vacuumcombined with a supply of arc-absorbing oil 5.

In the Figs. 3 and 4 It show the receptacle in the form of an uprightcylinder, hermetically sealed, and provided with an integral open top'cup or reservoir 1 formed on the interior vertical wall of thereceptacle thereof and filled with mercury 3. One of the terminals, B,is led down through the top of the receptacle into the open top of thecup and into contact with the mercury therein, while the other terminal,G, is led up through the bottom of the receptacle and throughthe bottomof the cup into contact with the mercury therein contained.

When an excess of current occurs, the

mercury 3is thrown out over the open top I of the cup 1, breaking theconnection between the two terminals. By first turning the receptacleupside down and then right side up again, the cup may be refilled, and

the circuit through the terminals reestablished,

The terminals should be of suilicient strength and stillness to preventtheir being bent or thrown out of their proper position, to contact withthe mercury, when the receptacle is being rotated orturned end for end,

The capacity of the reservoir or cup in my breaker is regulated toaccommodate a unit or quantity of mercury sufficientto carry the normalcurrent in the circuit.

It is evident from the foregoing that my improved circuit-breaker is aninexpensive, convenient and practically indestructible device,WillGhNYlll adequately protect the circuit, and through which thecircuit may be restored almost instantaneously, without having to supplyany newelementor portion, and even without removing the device from itsplace in the circuit. 1 What 1 desire to claim is-' 1. An electriccircuit breaker comprising a hermetically sealed receptacle, areservoircontained in said receptacle and having an open. top 'elevatedabove the bottom of the latter, a pair of line terminals leadingnee s-oethrough the walls of said receptacle and into the ends of said reservoirand a filling of;

fluid conductor for said'reservoir normally I electrically connectingsaid llne terminals open top normally elevated above the bottomof saidreceptacle, a pair of line terminals leading through the walls of saidreceptacle and extending into the ends of said'reservoir, and a supplyof fluid conductor in said receptacle whereby said reservoir may befilled with said conductor and the terminals electrically connected byinverting said receptacle and allowing said fluid conductor to How intothe reservoir over the open top thereof, and in case of an abnormal risein current said fluid conductor is expelled from said reservoir andfalls to the bottom or" said receptacle, thus breaking said electricalconnection.

8, in combination. with contact members interposed in an electriccircuit, a circuit breaker having its extremities mounted in saidmembers and rotatable therein, said circuit breaker consisting of ahermetically closed receptacle provided with an open top reservoir inthe interior thereof, terminals connected to said members and leadingthrough the walls of said receptacle into the-ends of said reservoir,and at filling of fluid conductor for said reservoir normally connectingsaid terminals electrically together but adapted to be expelled fromsaid reservoir to break said connectionhwhen an abnormal use of currentoccurs, said reservoir being refilled and said electrical connection ofsaid terminals being restored by rotating said receptacle, substantiallyas described. v/

Signed Pittsburgh, Pennsylvania, this 30th vday October, 1915, FREMONTJ. cLnAvnn.

at of

